To supply heat to industrial furnaces, ovens, and other heat-utilizing installations, such as boilers and the like, burners accepting various types of fuel are used, and, to increase their efficiency, the combustion air is preheated. Recuperative preheating is frequently employed, that is, the exhaust or combustion gases which are still hot are used, in a heat exchanger, to transfer some of their heat to the combustion air to be supplied to the burner - see, for example, German Published Patent Application DE-OS 27 42 070, to which the referenced U.S. Ser. No. 941,263 corresponds. These recuperative burner installations are so arranged that at least a portion of the exhaust gases is returned to the immediate vicinity of the burner itself. A heat exchanger, operating as a recuperator and forming part of the burner assembly, transfer at least a portion of the exhaust gas heat to the combustion air being supplied to the burner. Approximately 60% of the exhaust gas heat can be recuperated in this way. The burner may be operated, for example, by natural gas, coal gas, or oil. Burner installations arranged for fluid energy use would, however, become excessively complex if a greater percentage of exhaust gas heat were to be recovered. The reason therefor is the limited space available, particularly for heat exchange surfaces of the recuperator. The heat capacity of the stream of exhaust gas is higher than that of the combustion air being supplied to the burner. The remaining heat in the exhaust gases, which will have a temperature of between 300.degree. to 600.degree. C., is lost.